When you select a component on a form at design time, the Object Inspector displays its published properties and (when appropriate) allows you to edit them. Use the Tab key to toggle between the left-hand Property column and the right-hand Value column. When the cursor is in the Property column, you can navigate to any property by typing the first letters of its name. For properties of Boolean or enumerated types, you can choose values from a drop-down list or toggle their settings by double-clicking in Value column. 

If a plus (+) symbol appears next to a property name, clicking the plus symbol or typing '+' when the property has focus displays a list of subvalues for the property. Similarly, if a minus (-) symbol appears next to the property name, clicking the minus symbol or typing '-' hides the subvalues. 

By default, properties in the Legacy category are not shown; to change the display filters, right-click in the Object Inspector and choose View.  

When more than one component is selected, the Object Inspector displays all properties—except Name—that are shared by the selected components. If the value for a shared property differs among the selected components, the Object Inspector displays either the default value or the value from the first component selected. When you change a shared property, the change applies to all selected components. 

Changing code-related properties, such as the name of an event handler, in the Object Inspector automatically changes the corresponding source code. In addition, changes to the source code, such as renaming an event handler method in a form class declaration, is immediately reflected in the Object Inspector.